Click here to Find a Contractor in your area.
Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit

Steam system wet return near PVC pipe

CLamb Member Posts: 88
I want to replace my cast iron sewer piping with PVC. However the wet return of the steam heating system runs parallel to it a few inches away at crossing it at right angles less than an inch away at two places. Is the heat from the return going to adversely affect the PVC? If so, how can I best insulate it?


  • Jamie Hall
    Jamie Hall Member Posts: 16,306
    Shouldn't be a problem. A wet return should never be much above 140 F or so and usually a lot less -- barely warm in many cases (if it is, go find the leaking trap!). PVC can take that.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • RobG
    RobG Member Posts: 1,850
    Why are you replacing the cast iron?
  • Mad Dog_2
    Mad Dog_2 Member Posts: 3,471
    I wouldn't be too concerned next to a wet return. Steam main..another story. Mad Dog
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • KC_Jones
    KC_Jones Member Posts: 4,656
    RobG said:

    Why are you replacing the cast iron?

    I was wondering the same thing. The way the OP words it, it sounds like they want to replace it "just because".
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • CLamb
    CLamb Member Posts: 88
    RobG said:

    Why are you replacing the cast iron?

    Because it has developed major cracks due to shifting of the supports.
  • RobG
    RobG Member Posts: 1,850
    As Jamie said, it shouldn't be a problem. If you are worried you can insulate that section of the return.